Avoid peer notification when peer is offline, tune retries (#16737)

cmd/peer-rest-client.go

@@ -57,6 +57,10 @@ func (client *peerRESTClient) call(method string, values url.Values, body io.Rea
 // permanently. The only way to restore the connection is at the xl-sets layer by xlsets.monitorAndConnectEndpoints()
 // after verifying format.json
 func (client *peerRESTClient) callWithContext(ctx context.Context, method string, values url.Values, body io.Reader, length int64) (respBody io.ReadCloser, err error) {
+	if client == nil || !client.IsOnline() {
+		return nil, errPeerNotReachable
+	}
+
 	if values == nil {
 		values = make(url.Values)
 	}